Who is Walter Cunningham jr?

He is a poor farmer and Scouts classmate. Scout gets mad at him and rubs his nose in the dirt. His family doesn't take anything they can't pay back. Jem invites him to their place to eat lunch and he eats a lot, Scout gets angry at him for eating so much and covering his plate in syrup. On the first day of school he came in with no shoes on and he had hookworms from not having shoes and walking around in the barn barefoot.